My guess is communities ends up similar to subreddits.
Steemit never really was meant to be a Facebook type site. They always intended to focus upon reddit.
I agree, something like this could be a great addition to the STEEM blockchain. I have no idea how many people are on that site, but coming into an ecosystem like STEEM might be a benefit to anyone.
I read a post that talked about the developers looking to make the system be able to handle 100M people....that means there are parties who expect a ton of growth.
Any organization would be well served by that.
It probably will head towards subbreddits in terms of design which would leave a gap in the market for a more social site which minds seems to be. I think being an early adopter for a SMT could be great for it as they would probably get a lot of users from Steemit who are more interested in that type of social media but who are involved with the STEEM blockchain already.
It would make perfect sense to me to use minds as my front site and just share any good blogs that I create on Steemit which would increase my exposure across both really. It would be an interesting experiment if nothing else as their site is already tokenised really so they would have any easy way to monetize them with STEEM.